This invention relates to an electronic musical instrument and, more particularly, to an electronic musical instrument capable of producing musical tones from a plurality of tone forming systems in a mutually different manner.
In a conventional electronic musical instrument, a musical tone is produced in a certain predetermined tone production mode. For example, production of a tone is started upon depression of a key, sustained while the key is kept depressed and caused to decay after release of the key. Assuming, for another example, a case where a piano tone is simulated, the production of the tone is started at a maximum level and caused to decay thereafter. In this manner, the tone production by the conventional electronic musical instrument tends to be a monotonous one which solely depends upon manipulation of the key
It is therefore an object of the present invention to provide an electronic musical instrument capable of producing an intricate musical tone effect by providing a plurality of musical tone forming system which have mutually different tone production modes. According to one aspect of the invention, the instrument employs one tone production mode in which a musical tone is intermittently produced at a regular interval and another tone production mode in which a musical tone is continuously produced. By separately controlling the tone production in the different tone forming systems in accordance with the above described tone production modes, the musical tone produced in these different tone production modes are mixed together and an intricate musical tone effect is thereby produced. Further, it is possible, according to another aspect of the invention, to control the tone production in such a manner that a plurality of tones are produced simultaneously in one musical tone forming system while tones are produced one tone after another in another tone forming system so as to produce an intricate musical tone effect.
The timing of producing a tone intermittently can be automatically controlled by employing an automatic bass/chord performance control device or an automatic arpeggio performance control device. The automatic arpeggio performance is also called as "chord pyramid performance" because, in arpeggio, tones constituting a chord are sequentially produced one after another in the order of the tone pitch of these tones with a result that the tone pitch of the produced tones rises and falls in the form of a pyramid.
Further, according to still another aspect of the invention a tone volume envelope of the intermittently produced tones can be switched to either of a percussion type envelope and a sustain type one. By such switching of the envelope, the musical tone effect of the produced tone may be varied.
The above and other objects and features of the invention will become apparent from the description made hereinbelow in conjunction with the accompanying drawings.